Electromyographic Activity Determines Task Difficulty for Robotic Laparoscopic Training Programs B. Brown-Clerk1, K-C Siu1, D. Katsavelis1, I. Lee1, D. Oleynikov2, and N. Stergiou1 1 HPER Biomechanics Lab, University of Nebraska at Omaha 2 Department of Surgery, University of Nebraska Medical Center; Email:
[email protected], web: http://biomech.unomaha.edu/ INTRODUCTION In 2003 there were approximately 770,000 inguinal hernia repairs in the United States [1]. Over 75% of those hernia repairs were completed using mesh-based methodologies, and only 14% were completed laparoscopically. Hernia repair using the da Vinci® Surgical System (Intuitive Surgical Inc) has been gaining popularity due to motion scaling, greater range-of-motion and enhanced dexterity. Since hernia repair is a common procedure performed by general surgeons [2], incorporating a similar training task will help improve a robotic training programs and the growth of robotic laparoscopy. In the present study such a novel task, mesh alignment, was developed and compared with two well-known and valid surgical tasks, needle passing b (Fig.1a) and suture tying (Fig.1b) [3]. Figure 1. We assessed difficulty of these tasks Needle Passing using electromyography (EMG). We and Suture hypothesized that the task difficulty Tying tasks. of the novel mesh alignment task would be similar to the other two.
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B
frequency is a measure of muscular fatigue [3]. EMG measures were compared between task using one-way repeated measures ANOVA.
Figure 3: The da Vinci Surgical System. The control Console (left) and the surgical robot (right) RESULTS AND DISCUSSION ST required a significantly greater amount of activity from the right FCR to tie each intracorporeal knot (Fig. 4). Both ST and MA had significantly greater EMG envelope of the right FCR and left ED compared to NP. In addition, ST and MA showed no significant differences for muscular activation, fatigue and overall activity.
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Figure 2: Mesh Alignment Task. A) Initial Position, B) Repositioning, C) Final Position. METHODS Five volunteers were recruited to participate in the study (2 males & 3 females, 28.8 ± 7.3 years old) and performed three trials in all tasks using the da Vinci® Surgical System (Fig.3). Needle passing (NP) required to accurately pass a 23 mm surgical needle through five designated points along an inanimate material in the horizontal plane (Fig.1a). Suture tying (ST) required to pass the surgical needle and then tie an intracorporeal knot at three designated points (Fig.1b). Mesh Alignment (MA) required to loosen a rolled mesh (Fig. 2A) and accurately align it onto the material platform’s designated points (Fig. 2B-C). EMG from two forearm muscles was collected using the DelSysTM Bagnoli system sampled at 1,000 Hz. Surface electrodes were placed at the flexor carpi radialis (FCR) and extensor digitorum (ED) on both arms. A custom MATLAB program was used to calculate the EMG measures of mean activation, envelope (integrated EMG over the entire trial) and median frequency. EMG envelope is a measure of overall muscular activity and the median
Figure 4: Overall Muscle Activity of NP, ST and MA Overall, the NP task showed significantly less muscle activity indicating that this task is the least difficult. Both ST and MA showed similar muscular activation and overall activity as well as the amount of muscle fatigue. As a result, ST and MA have an equivalent degree of difficulty. Incorporating the mesh alignment task in future robotic training programs will benefit by diversifying training situations and the need for hernia repair in robotic surgery. Biomechanical evaluations can assist in the development of better surgical training tasks for robotic–assisted surgery. ACKNOWLEDGEMENTS This work was supported by NIH (K25HD047194), NIDRR (H133G040118), and the Nebraska Research Initiative. REFERENCES 1. Rutkow IM et al. Surg Clin N Am 83, 1045-51, 2003. 2. Rutkow IM et al. Arch Surg 132, 983-990, 1997. 3. Narazaki K et al. Surg Endosc 20, 96-103, 2006.
